B1515

B1515

Signal Ground, Missing

Fault symptoms
Malfunction.
The control module may be malfunctioning.

Conditions
No ground connection at pin 37.

Check wiring harness
Jiggle the wiring harness at several points and in different directions to reveal intermittent breaks and short-circuits in the leads. Observe the multimeter, test lamp or diagnostic instrument during the test.






Diagnostic procedure

1. Check wiring for any break
- Separate the connector: TWICE control module: (632).






- Measure the resistance.
- Red test lead: TWICE control module: 37.






- Black test lead: grounding point G14.
- The reading should be 0 - 1 ohm

Test results OK?
YES
- Go to point 2.
NO
- Repair or replace the lead.
- Go to point 3.






2. Check the ground lead for a short-circuit to B+
- Turn the ignition key to ON.






- Measure the voltage.
- Red test lead: TWICE control module: 37.






- Black test lead: grounding point G14.
- The reading should be 0 - 1 V.

Test results OK?
YES
- Go to point 3.
NO
- Repair or replace the lead.
- Go to point 3.






3. Final check
- Delete the diagnostic trouble codes in all systems.






- Carry out a function check.
- Evaluate the function check.
- Check that the trouble code does not recur.

Has the trouble code recurred?
YES
- See "Before changing a control module." Before Changing A Control Module
NO
- The steps taken to rectify the fault were correct.